256909880 has 32 divisors (see below), whose sum is σ = 579957840. Its totient is φ = 102424320.

The previous prime is 256909859. The next prime is 256909883. The reversal of 256909880 is 88909652.

It is a super-2 number, since 2×256909880² = 132005372883228800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256909883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1820 + ... + 22740.

Almost surely, 2^256909880 is an apocalyptic number.

256909880 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256909880 is an abundant number, since it is smaller than the sum of its proper divisors (323047960).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256909880 is a wasteful number, since it uses less digits than its factorization.

256909880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21239 (or 21235 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 47.

The square root of 256909880 is about 16028.4085298572. The cubic root of 256909880 is about 635.7117940518.

The spelling of 256909880 in words is "two hundred fifty-six million, nine hundred nine thousand, eight hundred eighty".